How to recover lost notes after signing out of Apple Account and copying data?

I signed out of my account because me and my girlfriend wanted to see what the child accounts were like on Iphone, I ended up getting stuck in the child account and on my mac book I still never signed out, but some recent notes i made over a week ago but within like 2 months dissapeared. I have searched everything I can find online and Ive had no luck. I NEED THESE NOTES HELP IS NEEDED

[Re-Titled by Moderator]

Original Title: I HAVE LOST MANY IMPORTANT NOTES AFTER SIGINGG OUT OF APPLE ACCOUNT AND COPYING MY DATA.